Yes, two:
The expression inside the backquotes may exceed the kernel's capacity
for an exec(), although it's not likely to overflow the 256Kbytes
allowed in NetBSD. But, as is pointed out frequently, "the world is
not NetBSD", and other systems, such as SunOS, have a 20Kbyte limit
on total character length of all the arguments passed to an exec().
And what if your filename has any of ()[]*$\;! in it?
--*greywolf;
--
System V was a mistake.